sc4612b Semtech Corporation, sc4612b Datasheet
sc4612b
Related parts for sc4612b
sc4612b Summary of contents
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... SC4612B is optimized for applications requiring wide input supply range and low output voltages down to 500mV. SC4612B comes with a rich set of features such as regulated DRV supply, programmable soft-start, high current gate drivers, internal bootstrapping for driving high side N-channel MOSFET, shoot through protection, R sensing with hiccup over current protection ...
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... SC4612B PRELIMINARY ...
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... SC4612B PRELIMINARY ...
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... SC4612B PRELIMINARY ± ± ...
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... MLPD package and 2500 for SOIC package.. (3) Lead-free product. This product is fully WEEE and RoHS compliant. PHASE DH BST DRV DL GND FB Marking Information - SOIC nnnnnnn = Part Number (Example: SC4612B) yyww = Date Code (Example: 0752) xxxxx = Semtech Lot No. Example: A01E90101) 5 SC4612B PRELIMINARY ...
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... SC4612B PRELIMINARY & ...
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... Disable + Vcc - UVLO 800mV + FB - Vref PWM Low Side Enable S Q Rdson OCP R PWM Enable PWM Disable + SS - Vref+0.5 7 SC4612B PRELIMINARY BST TOP Side Gate Driver BST PWM DH DH PHASE OCP PHASE Low Side Gate Driver VCC PWM DL DL GND Error Amp ...
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... SC4612B will turn off the high side MOSFET gate drive, and the soft-start sequence will repeat. The soft-start duration is controlled by the value of the SS cap. If the SS pin is pulled below 0.5V, the SC4612B is disabled and draws a typical quiescent current of 5mA. Bias Generation A 4.5V to 10V (MAX) supply voltage is required to power up the SC4612B. This voltage could be provided by an external power supply or derived from VDD (VDD > ...
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... As a rule of thumb, the limit should be set at least x10 greater then the pk-pk ripple current. Whenever a high current peak is detected, SC4612B would first block the driving of the high side and low side MOSFET, and then discharge the soft-start capacitor. Discharge rate of the SS capacitor is 1/25 of the charge rate ...
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... MOSFET - see “overcurrent protection” information on page 11 in the DS_ON datasheet. 2007 Semtech Corp. DRV pin R3 130k ILIM pin Rb R2 10k PHASE pin C1 2pF x I DS_ON LOAD 20mV DS_ON LOAD DRIVE Vphase SC4612B PRELIMINARY SC4612 2.75V R4 260k OCP COMP +100mV C2 R5 5pF 10k = 100mV = 7.8V typ. www.semtech.com ...
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... OFF, and the low side driver is latched ON. This mode can only be reset by power supply cycling. ERROR AMPLIFIER DESIGN The SC4612B is a voltage mode buck controller that utilizes an externally compensated high bandwidth error amplifier to regulate output voltage. The power stage of the ...
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... ESR at half P2 Figure 2. Simplified asymptotic diagram of buck power stage and its compensated loop gain. Switching Frequency 200 300 400 500 600 700 Frequency, (kHz) Table 1 12 SC4612B PRELIMINARY Loop gain T( ω Z2 ω c ω p1 ω p2 ω ESR . OSC 800 ...
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... Cout only, and therefore, connections between Cout and the load must be short, wide copper areas to minimize inductance and resistance. 5) The SC4612B is best placed over a quiet ground plane area. Avoid pulse currents in the Cin, M1, M2 loop flowing in this area. GND should be returned to the ground plane close to the package and close to the ground side of (one of) the output capacitor(s) ...
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... Switching losses can be estimated by assuming a switching time assume 100ns then: or more generally, c) Body diode recovery losses are more difficult to estimate, but to a first approximation reasonable to assume 14 SC4612B PRELIMINARY R C ESR ...
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... Choosing low ESR input capacitors will help maximize ripple rating for a given size SC4612B PRELIMINARY C/W for the SO-8 are readily achievable ...
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... 2172H 2.2/ 10V 7 GND C 9 10/50V _cer Fsw =250k Current, (A) 16 SC4612B PRELIMINARY Vin=40V Vin=36V C14 A C14B 330/ 50V_AL 330/ 50V_AL L1 4. Vou t=5@20A C12 A C12B C13 A C13B 330 / 6.3V 330 / 6.3V 330 / 10/ 6.3V_cer ...
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... DH D1 MBR0540 10 BST C10 0.1 HAT2168H 2.2/10V 0 HAT2165H GND C9 180/4V_PosCap 22/25V_cer Fsw=500kHz Current, (A) 17 SC4612B PRELIMINARY + Vin=24V C14A C14B 470/35V_AL 470/35V_AL _ L1 1.5uH@22A + Vout=3.3@20A C12A C12B C13A C13B 180/4V 180/4V 10/6.3V_cer www.semtech.com ...
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... DRV 22 3.01k HAT2 168H 280 Current, (A) 18 SC4612B PRELIMINARY + =12V _ C10 82uH@ 13A + C11 V o ut=3.3V @ 10A + 100/6 www.semtech.com ...
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... Semtech Corp. D1 SD107WS U1 12 PHASE BST Q1 HAT2168H 2.2 HAT2168H GND C9 100/6.3_1210_cer R6 13.3k Fsw=1MHz R7 649 Current, (A) 19 SC4612B PRELIMINARY + Vin=5V _ C10 0.1 L1 0.47uH@15A + Vout = 1.25V @ 12A Vout=1.35@12A C11 100/6.3_1210_cer www.semtech.com ...
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... POWER MANAGEMENT Application Information (Cont.) Evaluation Board: 2007 Semtech Corp. Top layer and components view Bottom Layer: 20 SC4612B PRELIMINARY www.semtech.com ...
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... bxN bbb D/2 K DIM INCHES (.112 .075 Z H .055 G K .087 P .018 Y X .010 Y .037 Z .150 P 21 SC4612B PRELIMINARY DIMENSIONS INCHES MILLIMETERS DIM MIN NOM MAX MIN NOM MAX - - A .031 .039 0.80 1. .000 .002 0.00 0.05 A2 (.008) (0.20) b .006 .008 .010 ...
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... SC4612B PRELIMINARY DIMENSIONS INCHES MILLIMETERS NOM MAX MIN NOM MAX - - .053 .069 1.35 1. .004 .010 0.10 0. .049 .065 1.25 1. .012 .020 0.31 0. ...